Preventing HIV infection in women: a global health imperative.

Women account for approximately one-half of all human immunodeficiency virus (HIV) infections worldwide. Sexual transmission is the dominant mode of HIV transmission to women, and there is a concomitant associated epidemic of transmission to infants. The majority of HIV infections in women are in sub-Saharan Africa, with a disproportionate burden in young women <25 years of age. Acquisition and prevention of HIV infection in women is complex and influenced by biological, behavioral, and structural factors. Efforts to reduce the incidence of HIV infection among women in sub-Saharan African could play a substantial role in altering global trajectories of HIV infection. Increasing access to sexual and reproductive health services, addressing gender-based violence and social instability, reducing poverty and the need to engage in sex for survival, and encouraging greater male responsibility are critical short-to-medium-term interventions. Efforts to find a microbicide and HIV vaccine need to be matched with efforts to deepen understanding of acquisition of HIV in the female genital tract to inform development of targeted molecules for prevention of HIV infection.